Core 2 will provide the five projects with a number of unique advanced optical systems;collaborate with the project investigators in the design, execution, and analysis of animal experiments;and develop new instrumentation and methodology as needs arise. The Core will be established in Boston within the Wellman Center for Photomedicine at Massachusetts General Hospital (MGH), where the new techniques and pilot experiments will be carried out. However, routine intravital microscopy experiments will be carried out in Houston within the new CABIR building where ad-hoc facilities have been specifically designed. The Advanced Intravital Microscopy Core is lead by Dr. Yun with the collaboration of Dr. Richards-Kortum at Rice University and Dr. Lin. Dr. Yun (Ph.D. Physics) is an Assistant Professor at Harvard Medical School within the Wellman Center for Photomedicine of the Massachusetts General Hospital. The activity of the core will be co-developed in collaboration with Dr. Lin within the Wellman Center for Photomedicine Dr. Yun and Dr. Lin research groups comprise a total of about 20 postdoctoral fellows and graduate students, externally funded, and in the past 3 years have published papers in Nature, Nature Medicine, Nature Photonics, Blood, Journal of Experimental Medicine, as well as top optics journals. Dr. Richards-Kortum (Ph.D. Physics) is Stanley C. Moore Professor and chair of the Bioengineering Department at Rice University. The Advanced Intravital Microscopy Core will use its technological tools and expertise to (i) reconstruct the vascular architecture (diameter, length, tortuosity, permeability) and the hydrodynamic conditions (flow rate, shear stress at the wall) within the region of interest;(ii) to visualize the transport of nano- and micro-sized particles within the vasculature and tumor microenvironment measuring in particulat their rate of adhesion to the endothelium, rate of extravasation from the vascular compartment, rate of diffusion within the epithelium, rate of internalization and possible exocytosis from normal and tumor cells. The transport of nanoparticles will be analyzed using the miniature front-view probe via minimally-invasive laparotomy.